High work function transparent conductors

ABSTRACT

There is provided a transparent conductor including conductive nanoparticles and at least one of (a) a fluorinated acid polymer and (b) a semiconductive polymer doped with a fluorinated acid polymer. The nanoparticles are carbon nanoparticles, metal nanoparticles, or combinations thereof. The carbon and metal nanoparticles are selected from nanotubes, fullerenes, and nanofibers. The acid polymers are fluorinated or highly fluorinated and have acidic groups including carboxylic acid groups, sulfonic acid groups, sulfonimide groups, phosphoric acid groups, phosphonic acid groups, and combinations thereof. The semiconductive polymers comprise homopolymers and copolymers derived from monomers selected from substituted and unsubstituted thiophenes, pyrroles, anilines, and cyclic heteroaromatics, and combinations of those. The compositions may be used in organic electronic devices (OLEDs).

RELATED U.S. APPLICATIONS

This application claims priority to provisional application, Ser. No.60/694793, filed Jun. 28, 2005.

BACKGROUND INFORMATION

1. Field of the Disclosure

This disclosure relates in general to transparent conductors havingworkfunction greater than 4.7 eV for use in electronic devices.

2.Description of the Related Art

Organic electronic devices define a category of products that include anactive layer. Such devices convert electrical energy into radiation,detect signals through electronic processes, convert radiation intoelectrical energy, or include one or more organic semiconductor layers.

Organic light-emitting diodes (OLEDs) are organic electronic devicescomprising an organic layer capable of electroluminescence. OLEDscontaining conducting polymers can have the following configurationwhich may include additional optional layers, materials or compositions:

anode/buffer layer/EL material/cathode

The anode is typically any material that has the ability to inject holesinto the electroluminescent (“EL”) material, such as, for example,indium/tin oxide (ITO). The anode is optionally supported on a glass orplastic substrate. The buffer layer is typically an electricallyconducting polymer and facilitates the injection of holes from the anodeinto the EL material layer. EL materials include fluorescent compounds,fluorescent and phosphorescent metal complexes, conjugated polymers, andcombinations and mixtures thereof. The cathode is typically any material(such as, e.g., Ca or Ba) that has the ability to inject electrons intothe EL material. At least one of the anode or cathode is transparent orsemi-transparent to allow for light emission.

ITO is frequently used as the transparent anode. However, the workfunction of ITO is relatively low, typically in the range of 4.6 eV.This low work function results in less effective injection of holes intothe EL material. In some cases, the work function of ITO can be improved(i.e., raised) by surface treatment. However, these treatments aresometime not stable and result in reduced device lifetime.

It is known that conductive carbon nanotube (“CNT”) dispersions can beused to form transparent, conductive films. The films have conductivityof about 6×10³ S/cm (Science, p 1273-1276, vol 305, Aug. 27, 2004),which is similar to the conductivity of indium/tin oxide vapor-depositedon substrates. It is evident that CNT film could replace ITO as atransparent anode. However, the work function of CNT is in the samerange as that of ITO and is not high enough to inject holes to the lightemitting layer for OLEDs applications.

Thus, there is a continuing need for improved materials to formtransparent anodes.

SUMMARY

There is provided a transparent conductor comprising conductivenanoparticles and at least one of (a) a fluorinated acid polymer and (b)a semiconductive polymer doped with a fluorinated acid polymer.

In another embodiment, there is provided an electronic device comprisingthe transparent conductor.

The foregoing general description and the following detailed descriptionare exemplary and explanatory and are not restrictive of the disclsoureand the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated by way of example and not limitation in theaccompanying figures.

FIG. 1 is a diagram illustrating contact angle.

FIG. 2 is a schematic diagram of an organic electronic device.

Skilled artisans appreciate that objects in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the objects in the figures may beenlarged relative to other objects to help to improve understanding ofembodiments.

DETAILED DESCRIPTION

There is provided a transparent conductor having workfunction greaterthan 4.7 eV comprising conductive nanoparticles and at least one of (a)a fluorinated acid polymer and (b) a semiconductive polymer doped with afluorinated acid polymer. The workfunction is defined as the energyrequired to remove an electron from the material to vaccum level. It istypically measured by Ultraviolet Photoemssion Spectroscopy. It can alsobe obtained by the Kelvin probe technique.

Many aspects and embodiments are described herein and are exemplary andnot limiting. After reading this specification, skilled artisans willappreciate that other aspects and embodiments are possible withoutdeparting from the scope of the invention.

As used herein, the term “transparent” refers to a material whichtransmits at least 50% of incident light, in the visible range. The term“conductive nanoparticles” refers to materials which have one or moredimension less than 100 nm, and which, when formed into a film, have aconductivity greater than 1 S/cm. It is understood that the particlescan have any shape, including circular, rectangular, polygonal, fibril,and irregular shapes. The term “fluorinated acid polymer” refers to apolymer having acidic groups, where at least some of the hydrogens havebeen replaced by fluorine. This fluorination may occur on the polymerbackbone, on side chains attached to the backbone, pendant groups, orcombinations of these. The term “acidic group” refers to a group capableof ionizing to donate a hydrogen ion to a base to form a salt. As usedherein, the term “semiconductive polymer” refers to any polymer oroligomer which is inherently or intrinsically capable of electricalconductivity without the addition of carbon black or conductive metalparticles. The term “polymer” encompasses homopolymers and copolymers.Copolymers may be formed of monomers having different structures ormonomers of the same structure with different substituents. The term“doped” is intended to mean that the semiconductive polymer has apolymeric counterion derived from a polymeric acid to balance the chargeon the conductive polymer.

1. Conductive Nanoparticles

In one embodiment, the conductive nanoparticles form films havingconductivity greater than 10 S/cm. In one embodiment, the conductivityis greater than 20 S/cm. In one embodiment, the conductive nanoparticleshave at least one dimension less than 50 nm. In one embodiment, theconductive nanoparticles have at least one dimension less than 30 nm.

Some exemplary types of conductive nanoparticles include, but are notlimited to, carbon nanotubes and nanofibers, metal nanoparticles, andmetal nanofibers.

Carbon nanotubes are elongated fullerenes where the walls of the tubescomprise hexagonal polyhedra formed by groups of six carbon atoms andare often capped at ends. Fullerenes are any of various cagelike, hollowmolecules composed of hexagonal and pentagonal groups of atoms thatconstitute the third form of carbon after diamond and graphite.Presently, there are three main approaches for the synthesis of single-and multi-walled carbon nanotubes. These include the electric arcdischarge of graphite rod (Journet et al. Nature 388: 756 (1997)), thelaser ablation of carbon (Thess et al. Science 273: 483 (1996)), and thechemical vapor deposition of hydrocarbons (Ivanov et al. Chem. Phys.Lett 223: 329 (1994); Li et al. Science 274: 1701 (1996)). Carbonnanotubes may be only a few nanometers in diameter, yet up to amillimeter long, so that the length-to-width aspect ratio is extremelyhigh. Carbon nanotubes also include nano-mat of carbon nanotubes. Carbonnanotubes and dispersions of carbon nanotubes in various solvents arecommercially available.

Carbon nanofibers are similar to carbon nanotubes in shape and diameter,but comprise carbon composites in a non-hollow, fibrous form, whereascarbon nanotubes are in the form of a hollow tube. Carbon nanofibers canbe formed using a method similar to the synthetic methods for carbonnanotubes.

The metal nanoparticles and nanofibers can be made from any conductivemetals, including, but not limited to, silver, nickel, gold, copper,palladium, and mixtures thereof. Metal nanoparticles are availablecommercially. The formation of nanofibers is possible through a numberof different approaches that are well known to those of skill in theart.

In one embodiment, the conductive nano-particles are in the form of anaqueous dispersion. In one embodiment, the aqueous dispersion furthercomprises a surfactant, which can be an anionic, cationic, or non-ionicsurfactant.

In one embodiment, the conductive nanoparticles are in the form of anon-aqueous dispersion.

2. Semiconductive Polymer

Any semiconductive polymer doped with a fluorinated acid polymer can beused in the new composition. In one embodiment, the doped semiconductivepolymer will form a film which has a conductivity of at least 10⁻⁷ S/cm.The semiconductive polymers suitable for the new composition can behomopolymers, or they can be copolymers of two or more respectivemonomers. The monomer from which the conductive polymer is formed, isreferred to as a “precursor monomer”. A copolymer will have more thanone precursor monomer.

In one embodiment, the semiconductive polymer is made from at least oneprecursor monomer selected from thiophenes, pyrroles, anilines, andpolycyclic aromatics. The polymers made from these monomers are referredto herein as polythiophenes, polypyrroles, polyanilines, and polycyclicaromatic polymers, respectively. The term “polycyclic aromatic” refersto compounds having more than one aromatic ring. The rings may be joinedby one or more bonds, or they may be fused together. The term “aromaticring” is intended to include heteroaromatic rings. A “polycyclicheteroaromatic” compound has at least one heteroaromatic ring.

In one embodiment, thiophene monomers contemplated for use to form thesemiconductive polymer comprise Formula I below:

wherein:

-   -   R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, amidosulfonate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, sulfur or oxygen atoms.

As used herein, the term “alkyl” refers to a group derived from analiphatic hydrocarbon and includes linear, branched and cyclic groupswhich may be unsubstituted or substituted. The term “heteroalkyl” isintended to mean an alkyl group, wherein one or more of the carbon atomswithin the alkyl group has been replaced by another atom, such asnitrogen, oxygen, sulfur, and the like. The term “alkylene” refers to analkyl group having two points of attachment.

As used herein, the term “alkenyl” refers to a group derived from analiphatic hydrocarbon having at least one carbon-carbon double bond, andincludes linear, branched and cyclic groups which may be unsubstitutedor substituted. The term “heteroalkenyl” is intended to mean an alkenylgroup, wherein one or more of the carbon atoms within the alkenyl grouphas been replaced by another atom, such as nitrogen, oxygen, sulfur, andthe like. The term “alkenylene” refers to an alkenyl group having twopoints of attachment.

As used herein, the following terms for substituent groups refer to theformulae given below:

“alcohol” —R³—OH “amido” —R³—C(O)N(R⁶)R⁶ “amidosulfonate”—R³—C(O)N(R⁶)R⁴—SO₃Z “benzyl” —CH₂—C₆H₅ “carboxylate” —R³—C(O)O—Z or—R³—O—C(O)—Z “ether” —R³—(O—R⁵)_(P)—O—R⁵ “ether —R³—O—R⁴—C(O)O—Zcarboxylate” or —R³—O—R⁴—O—C(O)—Z “ether sulfonate” —R³—O—R⁴—SO₃Z “estersulfonate” —R³—O—C(O)—R⁴—SO₃Z “sulfonimide” —R³—SO₂—NH—SO₂—R⁵ “urethane”—R³—O—C(O)—N(R⁶)₂

where all “R” groups are the same or different at each occurrence and

-   -   R³ is a single bond or an alkylene group    -   R⁴ is an alkylene group    -   R⁵ is an alkyl group    -   R⁶ is hydrogen or an alkyl group    -   p is 0 or an integer from 1 to 20    -   Z is H, alkali metal, alkaline earth metal, N(R⁵)₄ or R⁵        Any of the above groups may further be unsubstituted or        substituted, and any group may have F substituted for one or        more hydrogens, including perfluorinated groups. In one        embodiment, the alkyl and alkylene groups have from 1-20 carbon        atoms.

In one embodiment, in the thiophene monomer, both R¹ together form—O—(CHY)_(m)—O—, where m is 2 or 3, and Y is the same or different ateach occurrence and is selected from hydrogen, halogen, alkyl, alcohol,amidosulfonate, benzyl, carboxylate, ether, ether carboxylate, ethersulfonate, ester sulfonate, and urethane, where the Y groups may bepartially or fully fluorinated. In one embodiment, all Y are hydrogen.In one embodiment, the polythiophene ispoly(3,4-ethylenedioxythiophene). In one embodiment, at least one Ygroup is not hydrogen. In one embodiment, at least one Y group is asubstituent having F substituted for at least one hydrogen. In oneembodiment, at least one Y group is perfluorinated.

In one embodiment, the thiophene monomer has Formula I(a):

wherein:

-   -   R⁷ is the same or different at each occurrence and is selected        from hydrogen, alkyl, heteroalkyl, alkenyl, heteroalkenyl,        alcohol, amidosulfonate, benzyl, carboxylate, ether, ether        carboxylate, ether sulfonate, ester sulfonate, and urethane,        with the proviso that at least one R⁷ is not hydrogen, and    -   m is 2 or 3.

In one embodiment of Formula I(a), m is two, one R⁷ is an alkyl group ofmore than 5 carbon atoms, and all other R⁷ are hydrogen. In oneembodiment of Formula 1(a), at least one R⁷ group is fluorinated. In oneembodiment, at least one R⁷ group has at least one fluorine substituent.In one embodiment, the R⁷ group is fully fluorinated.

In one embodiment of Formula I(a), the R⁷ substituents on the fusedalicyclic ring on the thiophene offer improved solubility of themonomers in water and facilitate polymerization in the presence of thefluorinated acid polymer.

In one embodiment of Formula I(a), m is 2, one R⁷ is sulfonicacid-propylene-ether-methylene and all other R⁷ are hydrogen. In oneembodiment, m is 2, one R⁷ is propyl-ether-ethylene and all other R⁷ arehydrogen. In one embodiment, m is 2, one R⁷ is methoxy and all other R⁷are hydrogen. In one embodiment, one R⁷ is sulfonic aciddifluoromethylene ester methylene (—CH₂—O—C(O)—CF₂—SO₃H), and all otherR⁷ are hydrogen.

In one embodiment, pyrrole monomers contemplated for use to form thesemiconductive polymer comprise Formula II below.

where in Formula II:

-   -   R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, amidosulfonate, ether carboxylate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, sulfur or oxygen atoms;        and    -   R² is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, aryl, alkanoyl, alkylthioalkyl, alkylaryl, arylalkyl,        amino, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, ether sulfonate, ester sulfonate, and        urethane.

In one embodiment, R¹ is the same or different at each occurrence and isindependently selected from hydrogen, alkyl, alkenyl, alkoxy,cycloalkyl, cycloalkenyl, alcohol, benzyl, carboxylate, ether,amidosulfonate, ether carboxylate, ether sulfonate, ester sulfonate,urethane, epoxy, silane, siloxane, and alkyl substituted with one ormore of sulfonic acid, carboxylic acid, acrylic acid, phosphoric acid,phosphonic acid, halogen, nitro, cyano, hydroxyl, epoxy, silane, orsiloxane moieties.

In one embodiment, R² is selected from hydrogen, alkyl, and alkylsubstituted with one or more of sulfonic acid, carboxylic acid, acrylicacid, phosphoric acid, phosphonic acid, halogen, cyano, hydroxyl, epoxy,silane, or siloxane moieties.

In one embodiment, the pyrrole monomer is unsubstituted and both R¹ andR² are hydrogen.

In one embodiment, both R¹ together form a 6- or 7-membered alicyclicring, which is further substituted with a group selected from alkyl,heteroalkyl, alcohol, benzyl, carboxylate, ether, ether carboxylate,ether sulfonate, ester sulfonate, and urethane. These groups can improvethe solubility of the monomer and the resulting polymer. In oneembodiment, both R¹ together form a 6- or 7-membered alicyclic ring,which is further substituted with an alkyl group. In one embodiment,both R¹ together form a 6- or 7-membered alicyclic ring, which isfurther substituted with an alkyl group having at least 1 carbon atom.

In one embodiment, both R¹ together form —O—(CHY)_(m)—O—, where m is 2or 3, and Y is the same or different at each occurrence and is selectedfrom hydrogen, alkyl, alcohol, benzyl, carboxylate, amidosulfonate,ether, ether carboxylate, ether sulfonate, ester sulfonate, andurethane. In one embodiment, at least one Y group is not hydrogen. Inone embodiment, at least one Y group is a substituent having Fsubstituted for at least one hydrogen. In one embodiment, at least one Ygroup is perfluorinated.

In one embodiment, aniline monomers contemplated for use to form thesemiconductive polymer comprise Formula III below.

wherein:

-   -   a is 0 or an integer from 1 to 4;    -   b is an integer from 1 to 5, with the proviso that a+b=5; and        R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, amidosulfonate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, sulfur or oxygen atoms.

When polymerized, the aniline monomeric unit can have Formula IV(a) orFormula IV(b) shown below, or a combination of both formulae.

where a, b and R¹ are as defined above.

In one embodiment, the aniline monomer is unsubstituted and a=0.

In one embodiment, a is not 0 and at least one R¹ is fluorinated. In oneembodiment, at least one R¹ is perfluorinated.

In one embodiment, fused polycylic heteroaromatic monomers contemplatedfor use to form the semiconductive polymer have two or more fusedaromatic rings, at least one of which is heteroaromatic. In oneembodiment, the fused polycyclic heteroaromatic monomer has Formula V:

wherein:

-   -   Q is S or NR⁶;    -   R⁶ is hydrogen or alkyl;    -   R⁸, R⁹, R¹⁰, and R¹¹ are independently selected so as to be the        same or different at each occurrence and are selected from        hydrogen, alkyl, alkenyl, alkoxy, alkanoyl, alkythio, aryloxy,        alkylthioalkyl, alkylaryl, arylalkyl, amino, alkylamino,        dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl, alkylsulfonyl,        arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic        acid, phosphoric acid, phosphonic acid, halogen, nitro, nitrile,        cyano, hydroxyl, epoxy, silane, siloxane, alcohol, benzyl,        carboxylate, ether, ether carboxylate, amidosulfonate, ether        sulfonate, ester sulfonate, and urethane; and    -   at least one of R⁸ and R⁹, R⁹ and R¹⁰, and R¹⁰ and R¹¹ together        form an alkenylene chain completing a 5 or 6-membered aromatic        ring, which ring may optionally include one or more divalent        nitrogen, sulfur or oxygen atoms.

In one embodiment, the fused polycyclic heteroaromatic monomer hasFormula V(a), V(b), V(c), V(d), V(e), V(f), and V(g):

wherein:

-   -   Q is S or NH; and    -   T is the same or different at each occurrence and is selected        from S, NR⁶, O, SiR⁶ ₂, Se, and PR⁶;    -   R⁶ is hydrogen or alkyl.        The fused polycyclic heteroaromatic monomers may be substituted        with groups selected from alkyl, heteroalkyl, alcohol, benzyl,        carboxylate, ether, ether carboxylate, ether sulfonate, ester        sulfonate, and urethane. In one embodiment, the substituent        groups are fluorinated. In one embodiment, the substituent        groups are fully fluorinated.

In one embodiment, the fused polycyclic heteroaromatic monomer is athieno(thiophene). Such compounds have been discussed in, for example,Macromolecules, 34, 5746-5747 (2001); and Macromolecules, 35, 7281-7286(2002). In one embodiment, the thieno(thiophene) is selected fromthieno(2,3-b)thiophene, thieno(3,2-b)thiophene, andthieno(3,4-b)thiophene. In one embodiment, the thieno(thiophene) monomeris substituted with at least one group selected from alkyl, heteroalkyl,alcohol, benzyl, carboxylate, ether, ether carboxylate, ether sulfonate,ester sulfonate, and urethane. In one embodiment, the substituent groupsare fluorinated. In one embodiment, the substituent groups are fullyfluorinated.

In one embodiment, polycyclic heteroaromatic monomers contemplated foruse to form the copolymer in the new composition comprise Formula VI:

wherein:

-   -   Q is S or NR⁶;    -   T is selected from S, NR⁶, O, SiR⁶ ₂, Se, and PR⁶;    -   E is selected from alkenylene, arylene, and heteroarylene;    -   R⁶ is hydrogen or alkyl;        -   R¹² is the same or different at each occurrence and is            selected from hydrogen, alkyl, alkenyl, alkoxy, alkanoyl,            alkythio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,            amino, alkylamino, dialkylamino, aryl, alkylsulfinyl,            alkoxyalkyl, alkylsulfonyl, arylthio, arylsulfinyl,            alkoxycarbonyl, arylsulfonyl, acrylic acid, phosphoric acid,            phosphonic acid, halogen, nitro, nitrile, cyano, hydroxyl,            epoxy, silane, siloxane, alcohol, benzyl, carboxylate,            ether, ether carboxylate, amidosulfonate, ether sulfonate,            ester sulfonate, and urethane; or both R¹² groups together            may form an alkylene or alkenylene chain completing a 3, 4,            5, 6, or 7-membered aromatic or alicyclic ring, which ring            may optionally include one or more divalent nitrogen, sulfur            or oxygen atoms.

In one embodiment, the semiconductive polymer is a copolymer of aprecursor monomer and at least one second monomer. Any type of secondmonomer can be used, so long as it does not detrimentally affect thedesired properties of the copolymer. In one embodiment, the secondmonomer comprises no more than 50% of the copolymer, based on the totalnumber of monomer units. In one embodiment, the second monomer comprisesno more than 30%, based on the total number of monomer units. In oneembodiment, the second monomer comprises no more than 10%, based on thetotal number of monomer units.

Exemplary types of second precursor monomers include, but are notlimited to, alkenyl, alkynyl, arylene, and heteroarylene. Examples ofsecond monomers include, but are not limited to, fluorene, oxadiazole,thiadiazole, benzothiadiazole, phenylenevinylene, phenyleneethynylene,pyridine, diazines, and triazines, all of which may be furthersubstituted.

In one embodiment, the copolymers are made by first forming anintermediate precursor monomer having the structure A-B-C, where A and Crepresent first precursor monomers, which can be the same or different,and B represents a second precursor monomer. The A-B-C intermediateprecursor monomer can be prepared using standard synthetic organictechniques, such as Yamamoto, Stille, Grignard metathesis, Suzuki, andNegishi couplings. The copolymer is then formed by oxidativepolymerization of the intermediate precursor monomer alone, or with oneor more additional precursor monomers.

In one embodiment, the semiconductive polymer is a copolymer of two ormore precursor monomers. In one embodiment, the first precursor monomersare selected from a thiophene, a pyrrole, an aniline, and a polycyclicaromatic.

3. Fluorinated Acid Polymer

The fluorinated acid polymer (hereinafter referred to as “FAP”) can beany polymer which is fluorinated and has acidic groups. As used herein,the term “fluorinated” means that at least one hydrogen bonded to acarbon has been replaced with a fluorine. The term includes partiallyand fully fluorinated materials. In one embodiment, the fluorinated acidpolymer is highly fluorinated. The term “highly fluorinated” means thatat least 50% of the avialable hydrogens bonded to a carbon, have beenreplaced with fluorine. The term “acidic group” refers to a groupcapable of ionizing to donate a hydrogen ion to a Brønsted base to forma salt. The acidic groups supply an ionizable proton. In one embodiment,the acidic group has a pKa of less than 3. In one embodiment, the acidicgroup has a pKa of less than 0. In one embodiment, the acidic group hasa pKa of less than −5. The acidic group can be attached directly to thepolymer backbone, or it can be attached to side chains on the polymerbackbone. Examples of acidic groups include, but are not limited to,carboxylic acid groups, sulfonic acid groups, sulfonimide groups,phosphoric acid groups, phosphonic acid groups, and combinationsthereof. The acidic groups can all be the same, or the polymer may havemore than one type of acidic group.

In one embodiment, the FAP is organic solvent wettable (“wettable FAP”).The term “organic solvent wettable” refers to a material which, whenformed into a film, is wettable by organic solvents. The term alsoincludes polymeric acids which are not film-forming alone, but whichwhen doped into a semiconductive polymer will form a film which iswettable. In one embodiment, the organic solvent wettable material formsa film which is wettable by phenylhexane with a contact angle less than40°.

In one embodiment, the FAP is organic solvent non-wettable(“non-wettable FAP”). The term “organic solvent non-wettable” refers toa material which, when formed into a film, is not wettable by organicsolvents. The term also includes polymeric acids which are notfilm-forming alone, but which when doped into a semiconductive polymerwill form a film which is non-wettable. In one embodiment, the organicsolvent non-wettable material forms a film on which phenylhexane has acontact angle greater than 40°.

As used herein, the term “contact angle” is intended to mean the angle φshown in FIG. 1. For a droplet of liquid medium, angle φ is defined bythe intersection of the plane of the surface and a line from the outeredge of the droplet to the surface. Furthermore, angle φ is measuredafter the droplet has reached an equilibrium position on the surfaceafter being applied, i.e. “static contact angle”. The film of theorganic solvent wettable fluorinated polymeric acid is represented asthe surface. In one embodiment, the contact angle is no greater than35°. In one embodiment, the contact angle is no greater than 30°. Themethods for measuring contact angles are well known.

In one embodiment, the FAP is water-soluble. In one embodiment, the FAPis dispersible in water. In one embodiment, the FAP forms a colloidaldispersion in water.

In one embodiment, the polymer backbone is fluorinated.

Examples of suitable polymeric backbones include, but are not limitedto, polyolefins, polyacrylates, polymethacrylates, polyimides,polyamides, polyaramids, polyacrylamides, polystyrenes, and copolymersthereof. In one embodiment, the polymer backbone is highly fluorinated.In one embodiment, the polymer backbone is fully fluorinated.

In one embodiment, the acidic groups are selected from sulfonic acidgroups and sulfonimide groups. In one embodiment, the acidic groups areon a fluorinated side chain. In one embodiment, the fluorinated sidechains are selected from alkyl groups, alkoxy groups, amido groups,ether groups, and combinations thereof.

In one embodiment, the wettable FAP has a fluorinated olefin backbone,with pendant fluorinated ether sulfonate, fluorinated ester sulfonate,or fluorinated ether sulfonimide groups. In one embodiment, the polymeris a copolymer of 1,1-difluoroethylene and2-(1,1-difluoro-2-(trifluoromethyl)allyloxy)-1,1,2,2-tetrafluoroethanesulfonicacid. In one embodiment, the polymer is a copolymer of ethylene and2-(2-(1,2,2-trifluorovinyloxy)-1,1,2,3,3,3-hexafluoropropoxy)-1,1,2,2-tetrafluoroethanesulfonicacid. These copolymers can be made as the corresponding sulfonylfluoride polymer and then can be converted to the sulfonic acid form.

In one embodiment, the wettable FAP is homopolymer or copolymer of afluorinated and partially sulfonated poly(arylene ether sulfone). Thecopolymer can be a block copolymer. Examples of comonomers include, butare not limited to butadiene, butylene, isobutylene, styrene, andcombinations thereof.

In one embodiment, the wettable FAP is a homopolymer or copolymer ofmonomers having Formula VII:

where:

-   -   b is an integer from 1 to 5,    -   R¹³ is OH or NHR¹⁴, and    -   R¹⁴ is alkyl, fluoroalkyl, sulfonylalkyl, or        sulfonylfluoroalkyl.        In one embodiment, the monomer is “SFS” or SFSI” shown below:

After polymerization, the polymer can be converted to the acid form.

In one embodiment, the wettable FAP is a homopolymer or copolymer of atrifluorostyrene having acidic groups. In one embodiment, thetrifluorostyrene monomer has Formula VIII:

where:

-   -   W is selected from (CF₂)_(q), O(CF₂)_(q), S(CF₂)_(q),        (CF₂)_(q)O(CF₂)_(r), and SO₂(CF₂)_(q),    -   b is independently an integer from 1 to 5,    -   R¹³ is OH or NHR¹⁴, and    -   R¹⁴ is alkyl, fluoroalkyl, sulfonylalkyl, or        sulfonylfluoroalkyl.        In one embodiment, the monomer containing W equal to S(CF₂)_(q)        is polymerized then oxidized to give the polymer containing W        equal to SO₂(CF₂)_(q). In one embodiment, the polymer containing        R¹³ equal to F is converted its acid form where R¹³ is equal to        OH or NHR¹⁴.

In one embodiment, the wettable FAP is a sulfonimide polymer havingFormula IX:

where:

-   -   R_(f) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, or fluorinated        heteroarylene;    -   R_(g) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, fluorinated heteroarylene,        arylene, or heteroarylene; and    -   n is at least 4.        In one embodiment of Formula IX, R_(f) and R_(g) are        perfluoroalkylene groups.        In one embodiment, R_(f) and R_(g) are perfluorobutylene groups.        In one embodiment, R_(f) and R_(g) contain ether oxygens. In one        embodiment, n is greater than 20.

In one embodiment, the wettable FAP comprises a fluorinated polymerbackbone and a side chain having Formula X:

where:

-   -   R_(g) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, fluorinated heteroarylene,        arylene, or heteroarylene;    -   R¹⁵ is a fluorinated alkylene group or a fluorinated        heteroalkylene group;    -   R¹⁶ is a fluorinated alkyl or a fluorinated aryl group; and    -   p is 0 or an integer from 1 to 4.

In one embodiment, the wettable FAP has Formula XI:

where:

-   -   R¹⁶ is a fluorinated alkyl or a fluorinated aryl group;    -   a, b, c, d, and e are each independently 0 or an integer from 1        to 4; and    -   n is at least 4.

The synthesis of these fluorinated acid polymers has been described in,for example, A. Feiring et al., J. Fluorine Chemistry 2000, 105,129-135; A. Feiring et al., Macromolecules 2000, 33, 9262-9271; D. D.Desmarteau, J. Fluorine Chem. 1995, 72, 203-208; A. J. Appleby et al.,J. Electrochem. Soc. 1993, 140(1), 109-111; and Desmarteau, U.S. Pat.No. 5,463,005.

In one embodiment, the wettable FAP comprises at least one repeat unitderived from an ethylenically unsaturated compound having Formula XII:

-   -   wherein d is 0, 1, or 2;    -   R¹⁷ to R²⁰ are independently H, halogen, alkyl or alkoxy of 1 to        10 carbon atoms, Y, C(R_(f) ¹)(R_(f) ¹)OR²¹, R⁴Y or OR⁴Y;    -   Y is COE², SO₂ E², or sulfonimide;    -   R²¹ is hydrogen or an acid-labile protecting group;    -   R_(f) ¹ is the same or different at each occurrence and is a        fluoroalkyl group of 1 to 10 carbon atoms, or taken together are        (CF₂)_(e) where e is 2 to 10;    -   R⁴ is an alkylene group;    -   E² is OH, halogen, or OR⁷; and    -   R⁵ is an alkyl group;

with the proviso that at least one of R¹⁷ to R²⁰ is Y, R⁴Y or OR⁴Y. R⁴,R⁵, and R¹⁷ to R²⁰ may optionally be substituted by halogen or etheroxygen.

Some illustrative, but nonlimiting, examples of representative monomersof Formula XII are presented below as Formulas XIIa-XIIe:

wherein R²¹ is a group capable of forming or rearranging to a tertiarycation, more typically an alkyl group of 1 to 20 carbon atoms, and mosttypically t-butyl.

Compounds of Formula XII wherein d=0, (e.g., Formula XII-a), may beprepared by cycloaddition reaction of unsaturated compounds of structure(XIII) with quadricyclane (tetracyclo[2.2.1.0^(2,6)0^(3,5)]heptane) asshown in the equation below.

The reaction may be conducted at temperatures ranging from about 0° C.to about 200° C., more typically from about 30° C. to about 150 ° C. inthe absence or presence of an inert solvent such as diethyl ether. Forreactions conducted at or above the boiling point of one or more of thereagents or solvent, a closed reactor is typically used to avoid loss ofvolatile components. Compounds of structure (XII) with higher values ofd (i.e., d=1 or 2) may be prepared by reaction of compounds of structure(XII) with d=0 with cyclopentadiene, as is known in the art.

In one embodiment, the wettable FAP is a copolymer which also comprisesa repeat unit derived from at least one fluoroolefin, which is anethylenically unsaturated compound containing at least one fluorine atomattached to an ethylenically unsaturated carbon. The fluoroolefincomprises 2 to 20 carbon atoms. Representative fluoroolefins include,but are not limited to, tetrafluoroethylene, hexafluoropropylene,chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride,perfluoro-(2,2-dimethyl-1,3-dioxole),perfluoro-(2-methylene-4-methyl-1,3-dioxolane), CF₂═CFO(CF₂)_(t)CF═CF₂,where t is 1 or 2, and R_(f)″OCF═CF₂ wherein R_(f)″ is a saturatedfluoroalkyl group of from 1 to about ten carbon atoms. In oneembodiment, the comonomer is tetrafluoroethylene.

In one embodiment, the non-wettable FAP comprises a polymeric backbonehaving pendant groups comprising siloxane sulfonic acid. In oneembodiment, the siloxane pendant groups have the formula below:

—O_(a)Si(OH)_(b-a)R²² _(3-b)R²³R_(f)SO₃H

wherein:

-   -   a is from 1 to b;    -   b is from 1 to 3;    -   R²² is a non-hydrolyzable group independently selected from the        group consisting of alkyl, aryl, and arylalkyl;    -   R²³ is a bidentate alkylene radical, which may be substituted by        one or more ether oxygen atoms, with the proviso that R²³ has at        least two carbon atoms linearly disposed between Si and R_(f);        and    -   R_(f) is a perfluoralkylene radical, which may be substituted by        one or more ether oxygen atoms.        In one embodiment, the non-wettable FAP having pendant siloxane        groups has a fluorinated backbone. In one embodiment, the        backbone is perfluorinated.

In one embodiment, the non-wettable FAP has a fluorinated backbone andpendant groups represented by the Formula (XIV)

—O_(g)—[CF(R_(f) ²)CF—O_(h)]_(i)—CF₂CF₂SO₃H  (XIV)

wherein R_(f) ² is F or a perfluoroalkyl radical having 1-10 carbonatoms either unsubstituted or substituted by one or more ether oxygenatoms, h=0 or 1, i=0 to 3, and g=0 or 1.

In one embodiment, the non-wettable FAP has formula (XV)

where j≧0, k≧0 and 4≦(j+k)≦199, Q¹ and Q² are F or H, R_(f) ² is F or aperfluoroalkyl radical having 1-10 carbon atoms either unsubstituted orsubstituted by one or more ether oxygen atoms, h=0 or 1, i=0 to 3, g=0or 1, and E⁴ is H or an alkali metal. In one embodiment R_(f) ² is —CF₃,g=1, h=1, and i=1. In one embodiment the pendant group is present at aconcentration of 3-10 mol-%.

In one embodiment, Q¹ is H, k≧0, and Q² is F, which may be synthesizedaccording to the teachings of Connolly et al., U.S. Pat. No. 3,282,875.In another preferred embodiment, Q¹ is H, Q² is H, g=0, R_(f) ² is F,h=1, and i−1, which may be synthesized according to the teachings ofco-pending application Ser. No. 60/105,662. Still other embodiments maybe synthesized according to the various teachings in Drysdale et al., WO9831716(A1), and co-pending US applications Choi et al, WO 99/52954(A1),and application Ser. No. 60/176,881.

In one embodiment, the non-wettable FAP is a colloid-forming polymericacid. As used herein, the term “colloid-forming” refers to materialsthat are insoluble in water, and form colloids when dispersed into anaqueous medium. The colloid-forming polymeric acids typically have amolecular weight in the range of about 10,000 to about 4,000,000. In oneembodiment, the polymeric acids have a molecular weight of about 100,000to about 2,000,000. Colloid particle size typically ranges from 2nanometers (nm) to about 140 nm. In one embodiment, the colloids have aparticle size of 2 nm to about 30 nm. Any colloid-forming polymericmaterial having acidic protons can be used. In one embodiment, thecolloid-forming fluorinated polymeric acid has acidic groups selectedfrom carboxylic groups, sulfonic acid groups, and sulfonimide groups. Inone embodiment, the colloid-forming fluorinated polymeric acid is apolymeric sulfonic acid. In one embodiment, the colloid-formingpolymeric sulfonic acid is perfluorinated. In one embodiment, thecolloid-forming polymeric sulfonic acid is a perfluoroalkylenesulfonicacid.

In one embodiment, the non-wettable colloid-forming FAP. is ahighly-fluorinated sulfonic acid polymer (“FSA polymer”). “Highlyfluorinated” means that at least about 50% of the total number ofhalogen and hydrogen atoms in the polymer are fluorine atoms, an in oneembodiment at least about 75%, and in another embodiment at least about90%. In one embodiment, the polymer is perfluorinated. The term“sulfonate functional group” refers to either to sulfonic acid groups orsalts of sulfonic acid groups, and in one embodiment alkali metal orammonium salts. The functional group is represented by the formula—SO₃E⁵ where E⁵ is a cation, also known as a “counterion”. E⁵ may be H,Li, Na, K or N(R₁)(R₂)(R₃)(R₄), and R₁, R₂, R₃, and R₄ are the same ordifferent and are and in one embodiment H, CH₃ or C₂H₅. In anotherembodiment, E⁵ is H, in which case the polymer is said to be in the“acid form”. E⁵ may also be multivalent, as represented by such ions asCa⁺⁺, and Al⁺⁺⁺. It is clear to the skilled artisan that in the case ofmultivalent counterions, represented generally as M^(x+), the number ofsulfonate functional groups per counterion will be equal to the valence“x”.

In one embodiment, the FSA polymer comprises a polymer backbone withrecurring side chains attached to the backbone, the side chains carryingcation exchange groups. Polymers include homopolymers or copolymers oftwo or more monomers. Copolymers are typically formed from anonfunctional monomer and a second monomer carrying the cation exchangegroup or its precursor, e.g., a sulfonyl fluoride group (—SO₂F), whichcan be subsequently hydrolyzed to a sulfonate functional group. Forexample, copolymers of a first fluorinated vinyl monomer together with asecond fluorinated vinyl monomer having a sulfonyl fluoride group(—SO₂F) can be used. Possible first monomers include tetrafluoroethylene(TFE), hexafluoropropylene, vinyl fluoride, vinylidine fluoride,trifluoroethylene, chlorotrifluoroethylene, perfluoro(alkyl vinylether), and combinations thereof. TFE is a preferred first monomer.

In other embodiments, possible second monomers include fluorinated vinylethers with sulfonate functional groups or precursor groups which canprovide the desired side chain in the polymer. Additional monomers,including ethylene, propylene, and R—CH═CH₂ where R is a perfluorinatedalkyl group of 1 to 10 carbon atoms, can be incorporated into thesepolymers if desired. The polymers may be of the type referred to hereinas random copolymers, that is, copolymers made by polymerization inwhich the relative concentrations of the comonomers are kept as constantas possible, so that the distribution of the monomer units along thepolymer chain is in accordance with their relative concentrations andrelative reactivities. Less random copolymers, made by varying relativeconcentrations of monomers in the course of the polymerization, may alsobe used. Polymers of the type called block copolymers, such as thatdisclosed in European Patent Application No. 1 026 152 A1, may also beused.

In one embodiment, FSA polymers for use in the present invention includea highly fluorinated, and in one embodiment perfluorinated, carbonbackbone and side chains represented by the formula

—(O—CF₂CFR_(f) ³)_(a)—O—CF₂CFR_(f) ⁴SO₃E⁵

wherein R_(f) ³ and R_(f) ⁴ are independently selected from F, Cl or aperfluorinated alkyl group having 1 to 10 carbon atoms, a=0, 1 or 2, andE⁵ is H, Li, Na, K or N(R1)(R2)(R3)(R4) and R1, R2, R3, and R4 are thesame or different and are and in one embodiment H, CH₃ or C₂H₅. Inanother embodiment E⁵ is H. As stated above, E⁵ may also be multivalent.

In one embodiment, the FSA polymers include, for example, polymersdisclosed in U.S. Pat. No. 3,282,875 and in U.S. Pat. Nos. 4,358,545 and4,940,525. An example of preferred FSA polymer comprises aperfluorocarbon backbone and the side chain represented by the formula

—O—CF₂CF(CF₃)—O—CF₂CF₂SO₃E⁵

where X is as defined above. FSA polymers of this type are disclosed inU.S. Pat. No. 3,282,875 and can be made by copolymerization oftetrafluoroethylene (TFE) and the perfluorinated vinyl etherCF₂═CF—O—CF₂CF(CF₃)—O—CF₂CF₂SO₂F,perfluoro(3,6-dioxa-4-methyl-7-octenesulfonyl fluoride) (PDMOF),followed by conversion to sulfonate groups by hydrolysis of the sulfonylfluoride groups and ion exchanged as necessary to convert them to thedesired ionic form. An example of a polymer of the type disclosed inU.S. Pat. Nos. 4,358,545 and 4,940,525 has the side chain—O—CF₂CF₂SO₃E⁵, wherein E⁵ is as defined above. This polymer can be madeby copolymerization of tetrafluoroethylene (TFE) and the perfluorinatedvinyl ether CF₂═CF—O—CF₂CF₂SO₂F, perfluoro(3-oxa-4-pentenesulfonylfluoride) (POPF), followed by hydrolysis and further ion exchange asnecessary.

In one embodiment, the FSA polymers for use in this invention typicallyhave an ion exchange ratio of less than about 33. In this application,“ion exchange ratio” or “IXR” is defined as number of carbon atoms inthe polymer backbone in relation to the cation exchange groups. Withinthe range of less than about 33, IXR can be varied as desired for theparticular application. In one embodiment, the IXR is about 3 to about33, and in another embodiment about 8 to about 23.

The cation exchange capacity of a polymer is often expressed in terms ofequivalent weight (EW). For the purposes of this application, equivalentweight (EW) is defined to be the weight of the polymer in acid formrequired to neutralize one equivalent of sodium hydroxide. In the caseof a sulfonate polymer where the polymer has a perfluorocarbon backboneand the side chain is —O—CF₂—CF(CF₃)—O—CF₂—CF₂—SO₃H (or a salt thereof),the equivalent weight range which corresponds to an IXR of about 8 toabout 23 is about 750 EW to about 1500 EW. IXR for this polymer can berelated to equivalent weight using the formula: 50 IXR+344=EW. While thesame IXR range is used for sulfonate polymers disclosed in U.S. Pat.Nos. 4,358,545 and 4,940,525, e.g., the polymer having the side chain—O—CF₂CF₂SO₃H (or a salt thereof), the equivalent weight is somewhatlower because of the lower molecular weight of the monomer unitcontaining a cation exchange group. For the preferred IXR range of about8 to about 23, the corresponding equivalent weight range is about 575 EWto about 1325 EW. IXR for this polymer can be related to equivalentweight using the formula:

50 IXR+178=EW.

The FSA polymers can be prepared as colloidal aqueous dispersions. Theymay also be in the form of dispersions in other media, examples of whichinclude, but are not limited to, alcohol, water-soluble ethers, such astetrahydrofuran, mixtures of water-soluble ethers, and combinationsthereof. In making the dispersions, the polymer can be used in acidform. U.S. Pat. Nos. 4,433,082, 6,150,426 and WO 03/006537 disclosemethods for making of aqueous alcoholic dispersions. After thedispersion is made, concentration and the dispersing liquid compositioncan be adjusted by methods known in the art.

Aqueous dispersions of the colloid-forming polymeric acids, includingFSA polymers, typically have particle sizes as small as possible and anEW as small as possible, so long as a stable colloid is formed.

Aqueous dispersions of FSA polymer are available commericially asNafion® dispersions, from E. I. du Pont de Nemours and Company(Wilmington, Del.).

4. Preparing Doped Semiconductive Polymers

In one embodiment, the doped semiconductive polymers are formed byoxidative polymerization of the precursor monomer in the presence of atleast one FAP. The doped semiconductive polymers are abbreviatedhereinafter as “SCP/FAP”. The polymerization is generally carried out ina homogeneous aqeuous solution. In another embodiment, thepolymerization for obtaining the electrically conducting polymer iscarried out in an emulsion of water and an organic solvent. In general,some water is present in order to obtain adequate solubility of theoxidizing agent and/or catalyst. Oxidizing agents such as ammoniumpersulfate, sodium persulfate, potassium persulfate, and the like, canbe used. A catalyst, such as ferric chloride, or ferric sulfate may alsobe present. The resulting polymerized product will be a solution,dispersion, or emulsion of the doped semiconductive polymer.

In one embodiment, the method of making an aqueous dispersion of thesemiconductive polymer doped with FAP includes forming a reactionmixture by combining water, at least one precursor monomer, at least oneFAP, and an oxidizing agent, in any order, provided that at least aportion of the FAP is present when at least one of the precursor monomerand the oxidizing agent is added. It will be understood that, in thecase of semiconductive copolymers, the term “at least one precursormonomer” encompasses more than one type of monomer.

In one embodiment, the method of making an aqueous dispersion of thedoped semiconductive polymer includes forming a reaction mixture bycombining water, at least one precursor monomer, at least one FAP, andan oxidizing agent, in any order, provided that at least a portion ofthe FAP is present when at least one of the precursor monomer and theoxidizing agent is added.

In one embodiment, the method of making the doped semiconductive polymercomprises:

-   -   (a) providing an aqueous solution or dispersion of a FAP;    -   (b) adding an oxidizer to the solutions or dispersion of step        (a); and    -   (c) adding at least one precursor monomer to the mixture of step        (b).

In another embodiment, the precursor monomer is added to the aqueoussolution or dispersion of the FAP prior to adding the oxidizer. Step (b)above, which is adding oxidizing agent, is then carried out.

In another embodiment, a mixture of water and the precursor monomer isformed, in a concentration typically in the range of about 0.5% byweight to about 4.0% by weight total precursor monomer. This precursormonomer mixture is added to the aqueous solution or dispersion of theFAP, and steps (b) above which is adding oxidizing agent is carried out.

In another embodiment, the aqueous polymerization mixture may include apolymerization catalyst, such as ferric sulfate, ferric chloride, andthe like. The catalyst is added before the last step. In anotherembodiment, a catalyst is added together with an oxidizing agent.

In one embodiment, the polymerization is carried out in the presence ofco-dispersing liquids which are miscible with water. Examples ofsuitable co-dispersing liquids include, but are not limited to ethers,alcohols, alcohol ethers, cyclic ethers, ketones, nitriles, sulfoxides,amides, and combinations thereof. In one embodiment, the co-dispersingliquid is an alcohol. In one embodiment, the co-dispersing liquid is anorganic solvent selected from n-propanol, isopropanol, t-butanol,dimethylacetamide, dimethylformamide, N-methylpyrrolidone, and mixturesthereof. In general, the amount of co-dispersing liquid should be lessthan about 60% by volume. In one embodiment, the amount of co-dispersingliquid is less than about 30% by volume. In one embodiment, the amountof co-dispersing liquid is between 5 and 50% by volume. The use of aco-dispersing liquid in the polymerization significantly reducesparticle size and improves filterability of the dispersions. Inaddition, buffer materials obtained by this process show an increasedviscosity and films prepared from these dispersions are of high quality.

The co-dispersing liquid can be added to the reaction mixture at anypoint in the process.

In one embodiment, the polymerization is carried out in the presence ofa co-acid which is a Brønsted acid. The acid can be an inorganic acid,such as HCl, sulfuric acid, and the like, or an organic acid, such asacetic acid or p-toluenesulfonic acid. Alternatively, the acid can be awater soluble polymeric acid such as poly(styrenesulfonic acid),poly(2-acrylamido-2-methyl-1-propanesulfonic acid, or the like, or asecond fluorinated acid polymer, as described above. Combinations ofacids can be used.

The co-acid can be added to the reaction mixture at any point in theprocess prior to the addition of either the oxidizer or the precursormonomer, whichever is added last. In one embodiment, the co-acid isadded before both the precursor monomers and the fluorinated acidpolymer, and the oxidizer is added last. In one embodiment the co-acidis added prior to the addition of the precursor monomers, followed bythe addition of the fluorinated acid polymer, and the oxidizer is addedlast.

In one embodiment, the polymerization is carried out in the presence ofboth a co-dispersing liquid and a co-acid.

In the method of making the doped semiconductive polymer, the molarratio of oxidizer to total precursor monomer is generally in the rangeof 0.1 to 3.0; and in one embodiment is 0.4 to 1.5. The molar ratio ofFAP to total precursor monomer is generally in the range of 0.2 to 10.In one embodiment, the ratio is in the range of 1 to 5. The overallsolid content is generally in the range of about 0.5% to 12% in weightpercentage; and in one embodiment of about 2% to 6%. The reactiontemperature is generally in the range of about 4° C. to 50° C.; in oneembodiment about 20° C. to 35° C. The molar ratio of optional co-acid toprecursor monomer is about 0.05 to 4. The addition time of the oxidizerinfluences particle size and viscosity. Thus, the particle size can bereduced by slowing down the addition speed. In parallel, the viscosityis increased by slowing down the addition speed. The reaction time isgenerally in the range of about 1 to about 30 hours.

(a) pH Treatment

As synthesized, the aqueous dispersions of the doped semiconductivepolymers generally have a very low pH. When the semiconductive polymeris doped with a FAP, it has been found that the pH can be adjusted tohigher values, without adversely affecting the properties in devices. Inone embodiment, the pH of the dispersion can be adjusted to about 1.5 toabout 4. In one embodiment, the pH is adjusted to between 2 and 3. Ithas been found that the pH can be adjusted using known techniques, forexample, ion exchange or by titration with an aqueous basic solution.

In one embodiment, the as-formed aqueous dispersion of FAP-dopedsemiconductive polymer is contacted with at least one ion exchange resinunder conditions suitable to remove any remaining decomposed species,side reaction products, and unreacted monomers, and to adjust pH, thusproducing a stable, aqueous dispersion with a desired pH. In oneembodiment, the as-formed doped semiconductive polymer dispersion iscontacted with a first ion exchange resin and a second ion exchangeresin, in any order. The as-formed doped semiconductive polymerdispersion can be treated with both the first and second ion exchangeresins simultaneously, or it can be treated sequentially with one andthen the other. In one embodiment, the two doped semiconductive polymersare combined as-synthesized, and then treated with one or more ionexchange resins.

Ion exchange is a reversible chemical reaction wherein an ion in a fluidmedium (such as an aqueous dispersion) is exchanged for a similarlycharged ion attached to an immobile solid particle that is insoluble inthe fluid medium. The term “ion exchange resin” is used herein to referto all such substances. The resin is rendered insoluble due to thecrosslinked nature of the polymeric support to which the ion exchanginggroups are attached. Ion exchange resins are classified as cationexchangers or anion exchangers. Cation exchangers have positivelycharged mobile ions available for exchange, typically protons or metalions such as sodium ions. Anion exchangers have exchangeable ions whichare negatively charged, typically hydroxide ions.

In one embodiment, the first ion exchange resin is a cation, acidexchange resin which can be in protonic or metal ion, typically sodiumion, form. The second ion exchange resin is a basic, anion exchangeresin. Both acidic, cation including proton exchange resins and basic,anion exchange resins are contemplated for use in the practice of theinvention. In one embodiment, the acidic, cation exchange resin is aninorganic acid, cation exchange resin, such as a sulfonic acid cationexchange resin. Sulfonic acid cation exchange resins contemplated foruse in the practice of the invention include, for example, sulfonatedstyrene-divinylbenzene copolymers, sulfonated crosslinked styrenepolymers, phenol-formaldehyde-sulfonic acid resins,benzene-formaldehyde-sulfonic acid resins, and mixtures thereof. Inanother embodiment, the acidic, cation exchange resin is an organicacid, cation exchange resin, such as carboxylic acid, acrylic orphosphorous cation exchange resin. In addition, mixtures of differentcation exchange resins can be used.

In another embodiment, the basic, anionic exchange resin is a tertiaryamine anion exchange resin. Tertiary amine anion exchange resinscontemplated for use in the practice of the invention include, forexample, tertiary-aminated styrene-divinylbenzene copolymers,tertiary-aminated crosslinked styrene polymers, tertiary-aminatedphenol-formaldehyde resins, tertiary-aminated benzene-formaldehyderesins, and mixtures thereof. In a further embodiment, the basic,anionic exchange resin is a quaternary amine anion exchange resin, ormixtures of these and other exchange resins.

The first and second ion exchange resins may contact the as-formedaqueous dispersion either simultaneously, or consecutively. For example,in one embodiment both resins are added simultaneously to an as-formedaqueous dispersion of an electrically conducting polymer, and allowed toremain in contact with the dispersion for at least about 1 hour, e.g.,about 2 hours to about 20 hours. The ion exchange resins can then beremoved from the dispersion by filtration. The size of the filter ischosen so that the relatively large ion exchange resin particles will beremoved while the smaller dispersion particles will pass through.Without wishing to be bound by theory, it is believed that the ionexchange resins quench polymerization and effectively remove ionic andnon-ionic impurities and most of unreacted monomer from the as-formedaqueous dispersion. Moreover, the basic, anion exchange and/or acidic,cation exchange resins renders the acidic sites more basic, resulting inincreased pH of the dispersion. In general, about one to five grams ofion exchange resin is used per gram of semiconductive polymercomposition.

In many cases, the basic ion exchange resin can be used to adjust the pHto the desired level. In some cases, the pH can be further adjusted withan aqueous basic solution such as a solution of sodium hydroxide,ammonium hydroxide, tetra-methylammonium hydroxide, or the like.

5. Preparing High Workfunction Transparent Conductors

The new transparent conductors can be formed by first blending theconductive nanoparticles with the FAP or the SCP/FAP. This can beaccomplished by adding an aqueous dispersion of the conductivenanoparticles to an aqueous dispersion of the FAP or the SCP/FAP. In oneembodiment, the composition is further treated using sonication ormicrofluidization to ensure mixing of the components.

In one embodiment, one or both of the components are isolated in solidform. The solid material can be redispersed in water or in an aqueoussolution or dispersion of the other component. For example, conductivenanoparticle solids can be dispersed in an aqueous solution ordispersion of a semiconductive polymer doped with an FAP.

The solid tranparent conductor can then be formed using any liquiddeposition technique. Liquid deposition methods are well known.Continuous liquid deposition techniques, include but are not limited to,spin coating, gravure coating, curtain coating, dip coating, slot-diecoating, spray coating, and continuous nozzle coating. Discontinuousliquid deposition techniques include, but are not limited to, ink jetprinting, gravure printing, and screen printing. The conductor can be inthe form of a continuous or patterned layer.

6. Electronic Devices

In another embodiment of the invention, there are provided electronicdevices comprising at least one electroactive layer positioned betweentwo electrical contact layers, wherein the device further includes thenew transparent conductor. The term “electroactive” when referring to alayer or material is intended to mean a layer or material that exhibitselectronic or electro-radiative properties. An electroactive layermaterial may emit radiation or exhibit a change in concentration ofelectron-hole pairs when receiving radiation in the applications, forexample photovoltaic cells. In another embodiment of the invention,there are provided electronic devices where high workfunctiontransparent conductors function as electrode of drain, source and drainin field-effect transistor.

As shown in FIG. 2, one embodiment of a device, 100, has an anode layer110, an optional buffer layer 120, an electroactive layer 130, and acathode layer 150. Adjacent to the cathode layer 150 is an optionalelectron-injection/transport layer 140.

The new transparent conductor has particular utility as the anode 110.In one embodiment, the transparent conductor is formed by liquiddeposition methods. In one embodiment, the deposited transparentconductor films are heat-treated to coalesce the films.

The device may include a support or substrate (not shown) that can beadjacent to the anode layer 110 or the cathode layer 150. Mostfrequently, the support is adjacent the anode layer 110. The support canbe flexible or rigid, organic or inorganic. Examples of supportmaterials include, but are not limited to, glass, ceramic, metal, andplastic films.

The term “buffer layer” or “buffer material” is intended to meanelectrically conductive or semiconductive materials and may have one ormore functions in an organic electronic device, including but notlimited to, planarization of the underlying layer, charge transportand/or charge injection properties, scavenging of impurities such asoxygen or metal ions, and other aspects to facilitate or to improve theperformance of the organic electronic device. Buffer materials may bepolymers, oligomers, or small molecules, and may be in the form ofsolutions, dispersions, suspensions, emulsions, colloidal mixtures, orother compositions. In one embodiment, the buffer layer comprises holetransport material. Examples of hole transport materials for layer 120have been summarized for example, in Kirk-Othmer Encyclopedia ofChemical Technology, Fourth Edition, Vol. 18, p. 837-860, 1996, by Y.Wang. Both hole transporting molecules and polymers can be used.Commonly used hole transporting molecules include, but are not limitedto: 4,4′,4″-tris(N,N-diphenyl-amino)-triphenylamine (TDATA);4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine (MTDATA);N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine(TPD); 1,1-bis[(di-4-tolylamino) phenyl]cyclohexane (TAPC);N,N′-bis(4-methylphenyl)-N,N′-bis(4-ethylphenyl)-[1,1′-(3,3′-dimethyl)biphenyl]-4,4′-diamine(ETPD); tetrakis-(3-methylphenyl)-N,N,N′,N′-2,5-phenylenediamine (PDA);α-phenyl-4-N,N-diphenylaminostyrene (TPS); p-(diethylamino)benzaldehydediphenylhydrazone (DEH); triphenylamine (TPA);bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane (MPMP);1-phenyl-3[p-(diethylamino)styryl]-5-[p-(diethylamino)phenyl]pyrazoline(PPR or DEASP); 1,2-trans-bis(9H-carbazol-9-yl)cyclobutane (DCZB);N,N,N′,N′-tetrakis(4-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (TTB);N,N′-bis(naphthalen-1-yl)-N,N′-bis-(phenyl)benzidine (α-NPB); andporphyrinic compounds, such as copper phthalocyanine. Commonly used holetransporting polymers include, but are not limited to,poly(9,9,-dioctylfluorene-co-N-(4-butylphenyl) diphenylaminer), and thelike, polyvinylcarbazole, (phenylmethyl)polysilane,poly(dioxythiophenes), polyanilines, and polypyrroles. It is alsopossible to obtain hole transporting polymers by doping holetransporting molecules such as those mentioned above into polymers suchas polystyrene and polycarbonate.

Depending upon the application of the device, the electroactive layer130 can be a light-emitting layer that is activated by an appliedvoltage (such as in a light-emitting diode or light-emittingelectrochemical cell), a layer of material that responds to radiantenergy and generates a signal with or without an applied bias voltage(such as in a photodetector). In one embodiment, the electroactivematerial is an organic electroluminescent (“EL”) material. Any ELmaterial can be used in the devices, including, but not limited to,small molecule organic fluorescent compounds, fluorescent andphosphorescent metal complexes, conjugated polymers, and mixturesthereof. Examples of fluorescent compounds include, but are not limitedto, pyrene, perylene, rubrene, coumarin, derivatives thereof, andmixtures thereof. Examples of metal complexes include, but are notlimited to, metal chelated oxinoid compounds, such astris(8-hydroxyquinolato)aluminum (Alq3); cyclometalated iridium andplatinum electroluminescent compounds, such as complexes of iridium withphenylpyridine, phenylquinoline, or phenylpyrimidine ligands asdisclosed in Petrov et al., U.S. Pat. No. 6,670,645 and Published PCTApplications WO 03/063555 and WO 2004/016710, and organometalliccomplexes described in, for example, Published PCT Applications WO03/008424, WO 03/091688, and WO 03/040257, and mixtures thereof.Electroluminescent emissive layers comprising a charge carrying hostmaterial and a metal complex have been described by Thompson et al., inU.S. Pat. No. 6,303,238, and by Burrows and Thompson in published PCTapplications WO 00/70655 and WO 01/41512. Examples of conjugatedpolymers include, but are not limited to poly(phenylenevinylenes),polyfluorenes, poly(spirobifluorenes), polythiophenes,poly(p-phenylenes), copolymers thereof, and mixtures thereof.

Optional layer 140 can function both to facilitate electroninjection/transport, and can also serve as a confinement layer toprevent quenching reactions at layer interfaces. More specifically,layer 140 may promote electron mobility and reduce the likelihood of aquenching reaction if layers 130 and 150 would otherwise be in directcontact. Examples of materials for optional layer 140 include, but arenot limited to, metal chelated oxinoid compounds, such asbis(2-methyl-8-quinolinolato) (para-phenyl-phenolato)aluminum(III)(BAIQ), tetra(8-hydroxyquinolato)zirconium (ZrQ), andtris(8-hydroxyquinolato)aluminum (Alq₃); azole compounds such as2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole (PBD),3-(4-biphenylyl)-4-phenyl)-5-(4-t-butylphenyl)-1,2,4-triazole (TAZ), and1,3,5-tri(phenyl-2-benzimidazole)benzene (TPBI); quinoxaline derivativessuch as 2,3-bis(4-fluorophenyl)quinoxaline; phenanthroline derivativessuch as 9,10-diphenylphenanthroline (DPA) and2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (DDPA); and any one ormore combinations thereof. Alternatively, optional layer 140 may beinorganic and comprise BaO, LiF, Li₂O, or the like.

The cathode layer 150 is an electrode that is particularly efficient forinjecting electrons or negative charge carriers. The cathode layer 150can be any metal or nonmetal having a lower work function than the firstelectrical contact layer (in this case, the anode layer 110).

Materials for the cathode layer can be selected from alkali metals ofGroup 1 (e.g., Li, Na, K, Rb, Cs,), the Group 2 metals (e.g., Mg, Ca,Ba, or the like), the Group 12 metals, the lanthanides (e.g., Ce, Sm,Eu, or the like), and the actinides (e.g., Th, U, or the like).Materials such as aluminum, indium, yttrium, and combinations thereof,may also be used. Specific non-limiting examples of materials for thecathode layer 150 include, but are not limited to, barium, lithium,cerium, cesium, europium, rubidium, yttrium, magnesium, samarium, andalloys and combinations thereof.

The cathode layer 150 is usually formed by a chemical or physical vapordeposition process. In some embodiments, the cathode layer will bepatterned, as discussed above in reference to the anode layer 110.

Other layers in the device can be made of any materials which are knownto be useful in such layers upon consideration of the function to beserved by such layers.

In some embodiments, an encapsulation layer (not shown) is depositedover the contact layer 150 to prevent entry of undesirable components,such as water and oxygen, into the device 100. Such components can havea deleterious effect on the organic layer 130. In one embodiment, theencapsulation layer is a barrier layer or film. In one embodiment, theencapsulation layer is a glass lid.

It is understood that the device 100 may comprise additional layersthough such layers are not shown in FIG. 2. Other layers that are knownin the art or otherwise may be used. In addition, any of theabove-described layers may comprise two or more sub-layers or may form alaminar structure. Alternatively, some or all of anode layer 110 theoptional buffer layer 120, the electron transport layer 140, cathodelayer 150, and other layers may be treated, especially surface treated,to increase charge carrier transport efficiency or other physicalproperties of the devices. The choice of materials for each of thecomponent layers is preferably determined by balancing the goals ofproviding a device with high device efficiency with device operationallifetime considerations, fabrication time and complexity factors andother considerations appreciated by persons skilled in the art. It willbe appreciated that determining optimal components, componentconfigurations, and compositional identities would be routine to thoseof ordinary skill of in the art.

In various embodiments, the different layers have the following rangesof thicknesses: anode 110, 10-2000 Å, in one embodiment 50-500 Å;optional buffer layer 120, 50-2000 Å, in one embodiment 200-1000 Å;photoactive layer 130, 10-2000 Å, in one embodiment 100-1000 Å; optionalelectron transport layer 140, 50-2000 Å, in one embodiment 100-1000 Å;cathode 150, 200-10000 Å, in one embodiment 300-5000 Å. The location ofthe electron-hole recombination zone in the device, and thus theemission spectrum of the device, can be affected by the relativethickness of each layer. Thus the thickness of the electron-transportlayer should be chosen so that the electron-hole recombination zone isin the light-emitting layer. The desired ratio of layer thicknesses willdepend on the exact nature of the materials used.

In operation, a voltage from an appropriate power supply (not depicted)is applied to the device 100. Current therefore passes across the layersof the device 100. Electrons enter the organic polymer layer, releasingphotons. In some OLEDs, called active matrix OLED displays, individualdeposits of photoactive organic films may be independently excited bythe passage of current, leading to individual pixels of light emission.In some OLEDs, called passive matrix OLED displays, deposits ofphotoactive organic films may be excited by rows and columns ofelectrical contact layers.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

As used herein, the term “layer” is used interchangeably with the term“film” and refers to a coating covering a desired area. The meaning ofthe term is not limited by considerations of device or component size.

The area can be as large as an entire device or as small as a specificfunctional area such as the actual visual display, or as small as asingle sub-pixel. Layers and films can be formed by any conventionaldeposition technique, including vapor deposition, liquid deposition(continuous and discontinuous techniques), and thermal transfer.Continuous deposition techniques, inlcude but are not limited to, spincoating, gravure coating, curtain coating, dip coating, slot-diecoating, spray coating, and continuous nozzle coating. Discontinuousdeposition techniques include, but are not limited to, ink jet printing,gravure printing, and screen printing.

The term “work function” is intended to mean the minimum energy neededto remove an electron from a material to a point at infinite distanceaway from the surface.

Group numbers corresponding to columns within the periodic table of theelements use the “New Notation” convention as seen in the CRC Handbookof Chemistry and Physics, 81^(st) Edition (2000), where the groups arenumbered from left to right as 1-18.

Also, use of “a” or “an” are employed to describe elements andcomponents of the invention. This is done merely for convenience and togive a general sense of the invention. This description should be readto include one or at least one and the singular also includes the pluralunless it is obvious that it is meant otherwise.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of the present invention, suitable methods andmaterials are described below. All publications, patent applications,patents, and other references mentioned herein are incorporated byreference in their entirety. In case of conflict, the presentspecification, including definitions, will control. In addition, thematerials, methods, and examples are illustrative only and not intendedto be limiting.

EXAMPLES Example 1

This example illustrates preparation of an aqueous carbon nanotube(“CNT”) dispersion, and work function of the film spin-coated from thedispersion:

In this example, dispersing CNT in water was accomplished usingTriton-X-100 as a dispersing agent. Triton X-100 is a trade mark foroctylphenoxy polyethoxy ethanol. It is a non-ionic surfactant and has noinfluence in affecting Wf of CNT. A stock solution was made bydissolving 1.035 g Triton X-100 in 98.9922 g deionized water, whichamounts to 1.05% (w/w) in water. CNT used in this example is L0200single wall CNT (Laser/raw grade) purchased from CNI at Houston, Tex.,USA. 0.0709 g CNT were placed in a small glass jug to which 8.5802 g ofthe Triton X-100 solution and 25.5112 g de-ionized water were added. Themixture was subjected to sonication for 15 minutes continuously using aBranson Sonifier Model 450 having power set at #3. The glass jug wasimmersed in ice water contained in a tray to remove heat produced fromintense cavitation. The CNT formed a smooth, stable dispersion withoutany sign of sedimentation for many weeks.

The dispersion was spin-coated to form a film on a substrate forultraviolet photoelctron spectroscopy for measurement of work function(Wf). Wf energy level is usually determined from second electron cut-offwith respect to the position of vacuum level using He I (21.22 eV)radiation. Wf of the film was measured to be 4.5 eV to 4.6 eV, which isvery low for effective injection of holes to the light emitting materiallayer.

Example 2

This example illustrates preparation of an aqueous dispersion of CNTwith Nafion® having enhanced Wf of CNT. Nafion® is a trade name forpoly(perfluoroethylene sulfonic acid) from E. I. du Pont de Nemours andCompany, Wilmington, Del.:

L0200 single wall CNT (Laser/raw grade) in Example 1 was used in thisExample. Nafion® used for dispersing CNT is DE1020. A stock dispersionof the Nafion® was prepared first by mixing 19.7753 g DE1020 with162.119 g deionized water and 18.0151 g n-propanol. The resultingdispersion contained 1.13% Nafion® polymer. 32.5063 g of the dispersionwere mixed with 0.0688 g CNT in a glass jug. The mixture was thensubjected to sonication for 15 minutes continuously using a BransonSonifier Model 450 having power set at #3. The glass jug was immersed inice water contained in a tray to remove heat produced from intensecavitation. The CNT formed a smooth, stable dispersion without any signof sedimentation for many weeks.

The dispersion was spin-coated to form transparent film on a substratefor measurement of work function (Wf) by Ultraviolet PhotoelctronSpectroscopy. Wf energy level is usually determined from second electroncut-off with respect to the position of vacuum level using He I (21.22eV) radiation. Wf of the film was measured to be 6.2 eV. The Wf is muchhigher than that (4.5 eV to 4.6 eV) of CNT as illustrated in Example 1.

Example 3

This example illustrates preparation of an aqueous dispersion of CNTwith Nafion® and conductivity of CNT/ Nafion® film CNT used in thisexample is HIPco CE608, also purchased from CNI (CarbonNanotechnologies, Inc.) at Houston, Tex., USA. CE608 contains 3-4%residual catalyst. Nafion® used for dispersing CNT is DE1021. A stockdispersion of the Nafion® was prepared first by mixing 6.0263 g DE1021with 151.097 g deionized water and 16.797 g n-propanol. The resultingdispersion contained 0.39% Nafion® polymer. 34.9968 g of the dispersionwere mixed with 0.0707 g CNT in a glass jug. The mixture was thensubjected to sonication for 15 minutes continuously using a BransonSonifier Model 450 having power set at #3. The glass jug was immersed inice water contained in a tray to remove heat produced from intensecavitation. The CNT formed a smooth, stable dispersion without any signof sedimentation for many weeks.

A couple of drops of the dispersion were placed on a microscope slide toform a thin, transparent film. The thin film was painted with a roomtemperature silver paste to form two parallel lines as electrodes formeasurement of resistance. The resistance was converted to conductivityby taking a thickness of the film, separating the two electrodes alongthe length of the electrodes. Conductivity was determined to be 140 S/cmat room temperature. The conductivity is very close to that ofindium/tin oxide film.

Example 4

This example illustrates preparation of electrically conductingpoly(3,4, ethylenedioxythiophene) complexed with Nafion® for forming atop layer on a CNT film. A 12.0% (w/w) Nafion® with an EW of 1050 ismade using a procedure similar to the procedure in U.S. Pat. No.6,150,426, Example 1, Part 2, except that the temperature isapproximately 270° C.

In a 2000 mL reaction kettle are put 1088.2 g of 12% solid contentaqueous Nafion® (124.36 mmol SO₃H groups) dispersion, 1157 g water,0.161 g (0.311 mmol) iron(III)sulfate (Fe₂(SO₄)₃), and 1787 mL of 37%(w/w) HCl (21.76 mmol). The reaction mixture is stirred for 15 min at276 RPM using an overhead stirrer fitted with adouble-stage-propeller-type blade. Addition of 8.87 g (38.86 mmol)ammonium persulfate (Na₂S₂O₈) in 40 mL of water, and 3.31 mLethylenedioxythiophene (EDT) is started from separate syringes usingaddition rate of 3.1 mL/h for (NH₄)₂S₂O₈/water and 237 mL/h for EDTwhile continuous stirring at 245 RPM. The addition of EDT isaccomplished by placing the monomer in a syringe connected to a Teflon®tube that leads directly into the reaction mixture. The end of theTeflon® tube connecting the (NH₄)₂S₂O₈/water solution was placed abovethe reaction mixture such that the injection involved individual dropsfalling from the end of the tube. The reaction is stopped 7 hours afterthe addition of monomer has finished by adding 200 g of each LewatitMP62WS and Lewatit Monoplus S100 ion-exchange resins, and 250 g ofde-ionized water to the reaction mixture and stirring it further for 7hours at 130 RPM. The ion-exchange resin is finally filtered from thedispersion using Whatman No. 54 filter paper. The pH of thePEDOT-Nafion® dispersion is 3.2 and dried films derived from thedispersion have conductivity of 3.2×10⁻⁴S/cm at room temperature. UPShas shown that PEDOT-Nafion® has Wf of about 5.4 at that pH, which ismuch higher than Wf of the CNT film shown in Example 1.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed are not necessarily the order inwhich they are or must be performed.

In the foregoing specification, the concepts have been described withreference to specific embodiments. However, one of ordinary skill in theart appreciates that various modifications and changes can be madewithout departing from the scope of the invention as set forth in theclaims below. Accordingly, the specification and figures are to beregarded in an illustrative rather than a restrictive sense, and allsuch modifications are intended to be included within the scope ofinvention.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

It is to be appreciated that certain features of the invention whichare, for clarity, described above and below in the context of separateembodiments, may also be provided in combination in a single embodiment.Conversely, various features of the invention that are, for brevity,described in the context of a single embodiment, may also be providedseparately or in any subcombination. Further, references to valuesstated in ranges include each and every value within that range.

1. A transparent conductor having a work function greater than 4.7 eVconsisting of conductive nanoparticles and a fluorinated acid polymer.2. A transparent conductor of claim 1 wherein the nanoparticles areselected from carbon and metal nanoparticles and combinations thereof.3. A transparent conductor of claim 2 wherein the nanoparticles areselected from nanotubes, fullerenes, and nanofibers, and combinationsthereof.
 4. (canceled)
 5. (canceled)
 6. (canceled)
 7. (canceled) 8.(canceled)
 9. (canceled)
 10. A transparent conductor of claim 1 whereinthe fluorinated acid polymer has a backbone selected from the groupconsisting of polyolefins, polyacrylates, polymethacrylates, polyimides,polyamides, polyaramids, polyacrylamides, polystyrenes, and copolymersthereof.
 11. A transparent conductor of claim 10 wherein the fluorinatedacid polymer backbone is fluorinated.
 12. A transparent conductor ofclaim 11 wherein the fluorinated acid polymer has fluorinated pendantgroups selected from ether sulfonates, ester sulfonates, and ethersulfonimides.
 13. A transparent conductor of claim 10 wherein thefluorinated acid polymer consists of one or more independentlysubstituted or unsubstituted monomers selected from the group consistingof styrene sulfonic acids or sulfonated ether sulfones, trifluorostyrenesulfonates, sulfonimides, perfluoroalkyl sulfonate ethers, fusedpolycyclic fluoronated acids, and perfluoroalkyl sulfonic acid ethers.14. (canceled)
 15. (canceled)
 16. (canceled)
 17. A transparent conductorof claim 13 wherein the perfluoroalkyl sulfonate ethers have a structurerepresented by Formula XI:

where: R¹⁶ is a fluorinated alkyl or a fluorinated aryl group; a, b, c,d, and e are each independently 0 or an integer from 1 to 4; and n is atleast
 4. 18. (canceled)
 19. (canceled)
 20. A transparent conductor ofclaim 1 wherein the fluorinated acid polymer consists of polymeric acidscomprising functional groups selected from carboxylic, sulfonic,phosphoric, and phosphonic acid groups and sulfonimides, includingcombinations thereof.
 21. A transparent conductor of claim 20 whereinthe functional groups are present on the polymeric backbone, sidechains, pendant groups, or combinations thereof.
 22. A transparentconductor of claim 21 wherein the pendant groups include siloxanesulfonic acid.
 23. (canceled)
 24. A transparent conductor of claim 20wherein the fluorinated acid polymer is a colloid-forming polymericacid.
 25. A transparent conductor of claim 24 wherein the fluorinatedacid polymer is an FSA polymer.
 26. A transparent conductor having awork function greater than 4.7 eV consisting of conductivenanoparticles, a fluorinated acid polymer and a second polymer, thesecond polymer consisting of one or more independently substituted orunsubstituted monomers selected from alkenyls, alkynyls, arylenes, andheteroarylenes.
 27. A transparent conductor of claim 26 wherein theindependently substituted or unsubstituted monomers are selected fromfluorene, oxadiazoles, thiadiazolse, benzothiadiazoles,phenylenevinylenes, phenyleneethynylenes, pyridine, diazines, andtriazines.
 28. (canceled)
 29. (canceled)
 30. An electronic devicecomprising a transparent conductor of claim
 1. 31. (New/CurrentlyAmended) An electronic device of claim 30 comprising an anode layer,wherein the anode layer comprises the transparent conductor.
 32. Anelectronic device comprising a transparent conductor of claim
 26. 33. Anelectronic device of claim 32 comprising an anode layer, wherein theanode layer comprises the transparent conductor.